Umm.......
Yeah, the bug in the first level (reach the door and lose anyway) kind of kills the whole gaming experience. You might want to double-check your code before declaring a game ready to face the masses.
As for the graphics: maybe not the best, but at least you know what you're looking at. Might I suggest getting someone to help you with the graphics?
Once you fix that bug, this would be a decent first-attempt game. It mostly does what it's supposed to do (platforms work, etc.) Also, you may want to tweak the jump code a little. If I held the up arrow too long, the character would just bounce up and down. One jump per press, unless there's a double-jump mechanic coded in.